SSOE Group is an architecture and engineering firm with its Toledo, Ohio office at 1001 Madison Avenue and 17 U.S. office cities on its locations page. Most of its work is industrial: automotive, battery, semiconductor, chemical, food, glass and data center clients. An architectural side covers healthcare, higher education, K-12, aviation and government buildings. Services run from design and program management to site evaluation and commissioning. The site doesn’t state a founding year or headcount, though its copyright line reads 1948 to 2026. On the Ford Ohio Assembly Plant Expansion in Avon Lake, ENR credits SSOE as lead design firm and as structural, civil and MEP engineer, working with general contractor Rudolph Libbe Group.
The firm’s own history page fills in what the rest of the site leaves out. Al Samborn founded it in 1948 as A.H. Samborn & Associates after returning from the war, and the first contract was a material handling system design. Architects Erwin “Burrie” Otis Jr. and John H. V. Evans joined in 1958, producing the partnership name that the SSOE initials still come from. Incorporation followed in 1970, and the firm moved into its current downtown Toledo headquarters in 1976.
Growth has come largely through acquisition and through single long client relationships. Honda has been a client since 1980, starting with its first U.S. plant in Marysville, Ohio. The Nashville office arrived in 1987 with the acquisition of Pickney & Associates; Troy, Michigan opened in 1991; Columbus in 2008. The first international move was 2012, buying NKS Design Technologies in Mumbai, followed by León, Mexico in 2014. Stevens & Wilkinson, with offices in Atlanta and Columbia, South Carolina, joined in 2020, and Integrated Engineering Services in 2023, the year the firm turned 75. The Des Moines presence came with the SHYFT design team.
Headcount reached 1,500 in 2024, up from more than 1,100 in 2021. Catherine Myers became the firm’s first woman president and board chair in 2021.
The service list splits cleanly for owners. Architecture and engineering are the core; program and project management, site evaluation and master planning cover the front end before design starts; commissioning and qualification, hazardous materials consulting and sustainable design sit at the specialist end. Qualification is the one to note — for life sciences and semiconductor clients, validated systems are a regulatory requirement rather than an optional service, and few A/E firms carry it in house.
Rankings and performance claims are published and checkable: sixth among industrial-sector engineering firms and seventh on the top 40 engineering-architecture firms in BD+C’s 2026 Giants 400 report, 22nd largest private company in Central Ohio per Columbus Business First, a Great Workplace designation nine times and a Fortune Best Workplaces listing in 2025. The firm reports 95 percent of surveyed clients would recommend it, 150 clients retained over 20 years, and more than $2 billion in client cost savings since 2009. It is an active member of the Lean Construction Institute and partners with Autodesk on Construction Cloud.
